Document 1 (JP 2004-119286) discloses a light emitting device. This light emitting device includes a glass substrate, an ITO transparent electrode (anode electrode), a light emitting layer configured to emit light by means of EL, a back electrode (cathode electrode), and a diffractive optical element. In order to improve light extraction efficiency of the diffractive optical element, the diffractive optical element is provided on its surface with protrusions or grooves for preventing total reflection of the light emitted from the light emitting layer. For the purpose of suppressing an interference pattern caused by the diffractive optical element, the light emitting device is configured to emit white light with a discrete spectrum.
In Document 1, the white light emitted from the light emitting layer is deflected by the ITO transparent electrode, the glass electrode, and the diffractive optical element, when the white light comes into the ITO transparent electrode, the glass electrode, and the diffractive optical element, respectively. Therefore, the light emitting device of Document 1 suffers from chromatic aberration.